Biological Assembly 1  

 3D View: Structure

Global Symmetry: Helical - H  (3D View)
Global Stoichiometry: Homo 29-mer - A29 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 272.49 kDa 
• Atom Count: 18763 
• Residue Count: 2407 
• Unique protein chains: 1

2MME

Hybrid structure of the Shigella flexneri MxiH Type three secretion system needle

• DOI: 10.2210/pdb2MME/pdb
• BMRB: 18651
• EMDataResource: EMD-5352

• Classification: PROTEIN TRANSPORT
• Organism(s): Shigella flexneri
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2014-03-14 Released: 2014-10-08 
• Deposition Author(s): Demers, J.P., Habenstein, B., Loquet, A., Vasa, S.K., Becker, S., Baker, D., Lange, A., Sgourakis, N.G.

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Experimental Data Snapshot

• Method: SOLID-STATE NMR
• Conformers Calculated: 5000 
• Conformers Submitted: 10 
• Selection Criteria: target function 

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• Method: ELECTRON MICROSCOPY
• Resolution: 7.70 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

Literature

High-resolution structure of the Shigella type-III secretion needle by solid-state NMR and cryo-electron microscopy.

Demers, J.P., Habenstein, B., Loquet, A., Kumar Vasa, S., Giller, K., Becker, S., Baker, D., Lange, A., Sgourakis, N.G.

(2014) Nat Commun 5: 4976-4976

• PubMed: 25264107 
• DOI: 10.1038/ncomms5976
• Structures With Same Primary Citation


• PubMed Abstract: 
  

We introduce a general hybrid approach for determining the structures of supramolecular assemblies. Cryo-electron microscopy (cryo-EM) data define the overall envelope of the assembly and rigid-body orientation of the subunits while solid-state nuclear magnetic resonance (ssNMR) chemical shifts and distance constraints define the local secondary structure, protein fold and inter-subunit interactions. Finally, Rosetta structure calculations provide a general framework to integrate the different sources of structural information. Combining a 7.7-Å cryo-EM density map and 996 ssNMR distance constraints, the structure of the type-III secretion system needle of Shigella flexneri is determined to a precision of 0.4 Å. The calculated structures are cross-validated using an independent data set of 691 ssNMR constraints and scanning transmission electron microscopy measurements. The hybrid model resolves the conformation of the non-conserved N terminus, which occupies a protrusion in the cryo-EM density, and reveals conserved pore residues forming a continuous pattern of electrostatic interactions, thereby suggesting a mechanism for effector protein translocation.

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Related Citations: 

• Structure of a type III secretion needle at 7- angstrom resolution provides insights into its assembly and signaling mechanisms.
  Fujii, T., Cheung, M., Blanco, A., Kato, T., Blocker, A.J., Namba, K.
  (2012) Proc Natl Acad Sci U S A 109: 4461

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Organizational Affiliation: 

Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
MxiH	A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z, a, b, c	85	Shigella flexneri	Mutation(s): 0  Gene Names: mxiH
Find proteins for Q6XVY0 (Shigella flexneri) Go to UniProtKB:  Q6XVY0

Experimental Data & Validation

Experimental Data

• Method: SOLID-STATE NMR
• Conformers Calculated: 5000 
• Conformers Submitted: 10 
• Selection Criteria: target function 
• OLDERADO: 2MME Olderado

• Method: ELECTRON MICROSCOPY
• Resolution: 7.70 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2014-03-14 
• Released Date: 2014-10-08 
Deposition Author(s): Demers, J.P., Habenstein, B., Loquet, A., Vasa, S.K., Becker, S., Baker, D., Lange, A., Sgourakis, N.G.

Revision History 

• Version 1.0: 2014-10-08
  Type: Initial release
  
• Version 1.1: 2020-02-05
  Changes: Author supporting evidence, Data collection, Database references, Other